如何在Xcode中显示带有纹理的3D对象

import UIKit
import SceneKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // 创建一个SceneKit视图
        let sceneView = SCNView(frame: view.bounds)
        sceneView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view.addSubview(sceneView)

        // 创建一个SceneKit场景
        let scene = SCNScene()

        // 加载3D模型文件
        if let modelURL = Bundle.main.url(forResource: "model", withExtension: "obj") {
            if let model = try? SCNScene(url: modelURL, options: nil) {
                // 创建一个节点来显示模型
                let modelNode = SCNNode()
                for childNode in model.rootNode.childNodes {
                    modelNode.addChildNode(childNode)
                }

                // 创建一个材质，并设置纹理图像
                let material = SCNMaterial()
                material.diffuse.contents = UIImage(named: "texture.png")
                modelNode.geometry?.firstMaterial = material

                // 将模型节点添加到场景中
                scene.rootNode.addChildNode(modelNode)
            }
        }

        // 将场景设置为视图的场景
        sceneView.scene = scene

        // 配置视图
        sceneView.backgroundColor = UIColor.white
        sceneView.allowsCameraControl = true
        sceneView.showsStatistics = true
    }
}